1. Technical Field
The disclosure relates to a three-dimensional display device that utilizes manipulation of light corresponding to two-dimensional (2D) images.
2. Description of Related Art
In an attempt to improve upon traditionally generated 2D images, innovations have been conceived to accurately represent our 3D environment via electronic display devices.
Referring to FIG. 23, a commonly used 3D display system 100 includes a projection screen 101, a projector 102, a memory 103 and a mirror 105. The projection screen 101 is capable of rotating at high speed. The memory 103 stores images of an object, each image being a photograph taken from one particular viewing angle position of a range of viewing angle positions around the object; i.e., the range from 0° to 360°. Each image corresponds to a particular rotation angle (orientation) of the projection screen 101, also in the range from 0° to 360°. The projector 102 projects the images one after another onto the mirror 105, which reflects the images onto the rotating projection screen 101.
In detail, when the 3D display system 100 displays a representation of the object, the projection screen 101 rotates at high speed to become nearly invisible. During such rotation, when the projection screen 101 reaches a position (angular orientation) perpendicular to a given viewing angle of the object stored in the memory 103, the projector 102 projects the image corresponding to that viewing angle position onto the projection screen 101 via the mirror 105. When the projection screen 101 reaches a next adjacent position (angular orientation), such position is perpendicular to a next adjacent viewing angle of the object stored in the memory 103, and the projector 102 projects the image corresponding to that next adjacent viewing angle position onto the projection screen 101 via the mirror 105. Thus as the projection screen 101 continues to rotate, a series of images of the object are displayed on the projection screen 101 in quick succession. Very fast rotation of the projection screen 101, together with the projector 102 presenting the series of images in very fast succession, enable the image to appear to be a 3D image as seen by a human viewer.
However, a high performance motor is required to rotate the projection screen 101 at high speed, increasing costs and power consumption. In addition, in order that the projector 102 be one that is capable of switching images at the required high speed, costs are further increased. Furthermore, the 3D display system 100 requires a complex structure occupying a relatively large space.
Therefore, there is room for improvement within the art.